Europa’s icy waters may contain enough oxygen to support various kinds of lifeforms–including more than just the microbial kind.

We already know that Europa, arguably Jupiter’s most interesting moon, contains a global ocean that runs about 100 miles deep, with an icy crust on top, as Space.com reports. For years, scientists have theorized that the moon could support extraterrestrial life, at least in microbial form.

Richard Greenberg, a planetary scientist at the University of Arizona’s Lunar and Planetary Laboratory at Tucson, and the author of Unmasking Europa: The Search for Life on Jupiter’s Ocean Moon, explained in the article that an oxygen-rich layer of ice at the top could actually extend down much further than thought, and could reach the oceans underneath.

Greenberg found that as the ice on the base of the oxygenated crust melts, even with the most conservative assumptions, “after only a half-million years oxidant levels in the ocean would reach the minimum oxygen concentration seen in Earth’s oceans”–enough to support small crustaceans, according to the article.

“I was surprised at how much oxygen could get down there,” Greenberg said in the report. He added that we wouldn’t necessarily have to land a probe on the planet to detect the oxygen more directly, as telescope-based spectroscopy from Earth could help shed further light on the subject. (Image credit: NASA/JPL)